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Metallic hydrogen (MH) has been predicted to be metastable, a high temperature superconductor, and a powerful rocket propellant. If true, MH could have an enormous impact on society. We have produced MH in a diamond anvil cell and studied its metastability. At a temperature of 5 K, the load on the metallic hydrogen was stepwise reduced until the pressure was essentially zero. While turning the load or pressure down, the sample evidently transformed to the molecular phase and escaped; the hole in the gasket containing the MH closed. We were unable to determine this value of the metastability pressure. Metallic hydrogen was not observed to be metastable at zero pressure, with no uncertainty.

Abstract Polyethylene (C2H4)n was compressed to pressures between 10 and 30 GPa in a diamond anvil cell (DAC) and laser heated above 2500 K for approximately one second. This resulted in the chemical decomposition of the polymer into carbon and hydrocarbon reaction products. After quenching to ambient temperature, the decomposition products were measured in the DAC at pressures ranging from ambient to 29 GPa using a combination of x-ray diffraction (XRD) and small angle x-ray scattering (SAXS). XRD identified cubic diamond and methane as the predominant product species with their pressure–volume relationships exhibiting strong correlations to the diamond and methane equations of state. Length scales associated with the diamond products, obtained from SAXS measurements, indicate the formation of nanodiamonds with a radius of gyration between 12 and 35 nm consistent with 32–90 nm diameter spherical particles. These results are in good agreement with the predicted product composition under thermodynamic and chemical equilibrium.

Neuro-Linguistic Programming (NLP) has the potential to help language learners; however, it has received scant attention. Collingwood (2001), NLP is a technique to investigate the relationship between how our mind works (Neuro), how we communicant verbally and nonverbally (linguistic), and our patterns of behavior and feeling(program). The present study was an attempt to investigate the effect of NLP techniques on the writing ability of English as a Foreign Language. To achieve this goal, two intact classes of students were selected to form an experimental group (n=15) and a control group (n=15). A writing ability pre-test (based on the course content) was given to all participants. The participants in the experimental group were familiarized with NLP techniques to be able to implement these techniques in their writing. In the control group, the conventional approach to teaching was used. Comparing the results of the post-test results through ANCOVA, it was found that implementation of NLP techniques can significantly affect EFL learners' writing ability. Therefore, NLP can improve writing ability by improving various processes such as communication and information processing. Teachers, trainers and syllabus design can use it.

Conjugated polymers are a versatile class of electronic materials featured in a variety of next-generation electronic devices. The utility of such polymers is contingent in large part on their electrical conductivity, which depends both on the density of charge carriers (polarons) and on the carrier mobility. Carrier mobility, in turn, is largely controlled by the separation between the polarons and dopant counterions, as counterions can produce Coulombic traps. In previous work, we showed that large dopants based on dodecaborane (DDB) clusters were able to reduce Coulombic binding and thus increase carrier mobility in regioregular (RR) poly(3-hexylthiophene-2,5-diyl) (P3HT). Here, we use a DDB-based dopant to study the effects of polaron-counterion separation in chemically doped regiorandom (RRa) P3HT, which is highly amorphous. X-ray scattering shows that the DDB dopants, despite their large size, can partially order the RRa P3HT during doping and produce a doped polymer crystal structure similar to that of DDB-doped RR P3HT; Alternating Field (AC) Hall measurements also confirm a similar hole mobility. We also show that use of the large DDB dopants successfully reduces Coulombic binding of polarons and counterions in amorphous polymer regions, resulting in a 77% doping efficiency in RRa P3HT films. The DDB dopants are able to produce RRa P3HT films with a 4.92 S/cm conductivity, a value that is ∼200× higher than that achieved with 3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), the traditional dopant molecule. These results show that tailoring dopants to produce mobile carriers in both the amorphous and semicrystalline regions of conjugated polymers is an effective strategy for increasing achievable polymer conductivities, particularly in low-cost polymers with random regiochemistry. The results also emphasize the importance of dopant size and shape for producing Coulombically unbound, mobile polarons capable of electrical conduction in less-ordered materials.

This study explores the influence of electronic and ionic conductivities on the behavior of conjugated polymer binders through the measurement of entropic potential and heat generation in an operating lithium-ion battery. Specifically, the traditional poly(vinylidene fluoride) (PVDF) binder in LiNi0.8Co0.15Al0.05O2 (NCA) cathode electrodes was replaced with semiconducting polymer binders based on poly(3,4-propylenedioxythiophene). Two conjugated polymers were explored: one is a homopolymer with all aliphatic side chains, and the other is a copolymer with both aliphatic and ethylene oxide side chains. We have shown previously that both polymers have high electronic conductivity in the potential range of NCA redox, but the copolymer has a higher ionic conductivity and a slightly lower electronic conductivity. Entropic potential measurements during battery cycling revealed consistent trends during delithiation for all of the binders, indicating that the binders did not modify the expected NCA solid solution deintercalation process. The entropic signature of polymer doping to form the conductive state could be clearly observed at potentials below NCA oxidation, however. Operando isothermal calorimetric measurements showed that the conductive binders resulted in less Joule heating compared to PVDF and that the net electrical energy was entirely dissipated as heat. In a comparison of the two conjugated polymer binders, the heat dissipation was lower for the homopolymer binder at lower C-rates, suggesting that electronic conductivity rather than ionic conductivity was the most important for reducing Joule heating at lower rates, but that ionic conductivity became more important at higher rates.

To compare pregnancy outcomes after laparoscopic radiofrequency ablation and myomectomy.The ULTRA (Uterine Leiomyoma Treatment With Radiofrequency Ablation) study is an ongoing multicenter prospective cohort study with longitudinal follow-up up to 5 years comparing outcomes of radiofrequency ablation with myomectomy in premenopausal women older than age 21 years with symptomatic uterine leiomyomas. Participants were queried every 6 months after surgery to assess the incidence of pregnancy and pregnancy outcomes.Among 539 women enrolled in ULTRA, a total of 37 participants (mean age at first pregnancy 35.0±4.7 years) conceived 43 times as of March 2023 (22 radiofrequency ablation, 21 myomectomy). The average length of follow-up time after all procedures was 2.5±1.0 years. The baseline miscarriage rate in the study population was 33.3%. In participants who underwent radiofrequency ablation, 9 of 22 pregnancies (40.9%, 95% CI, 20.3-61.5%) ended in first-trimester miscarriage, 11 resulted in live births (50.0%, 95% CI, 29.1-70.9%), one resulted fetal death at 30 weeks of gestation, and one resulted in uterine rupture during miscarriage treatment with misoprostol 10 weeks after radiofrequency ablation. Among the live births in the radiofrequency ablation group, 45.5% were by vaginal delivery. In the myomectomy group, 9 of 21 pregnancies (42.9%, 95% CI, 21.7-64.0%) ended in first-trimester miscarriage and 12 resulted in live births (57.1%, 95% CI, 36.0-78.3%). There were no significant differences in the likelihood of live birth or miscarriage between the study groups.Full-term pregnancy and vaginal delivery are achievable after radiofrequency ablation of leiomyomas. However, in this interim analysis, the miscarriage rate in both radiofrequency ablation and myomectomy groups was higher than expected for women in this age group. Long-term data collection in the ongoing ULTRA study aims to further understand pregnancy outcomes after radiofrequency ablation compared with myomectomy.ClinicalTrials.gov, NCT0210094.

INTRODUCTION: Anti-amyloid therapies are at the forefront of efforts to treat Alzheimers disease (AD). Identifying amyloid risk factors may aid screening and intervention strategies. While veterans face increased exposure to risk factors, whether they face a greater neuropathologic amyloid burden is not well understood. METHODS: Male decedents donating to two Alzheimers Disease Research Center (ADRC) brain banks from 1986 to 2018 with categorized neuritic plaque density and neurofibrillary tangles (n = 597) were included. Using generalized ordered logistic regression we modeled each outcomes association with military history adjusting for age and death year. RESULTS: Having served in the military (60% of sample) is associated with post mortem neuritic amyloid plaque (for each comparison of higher to lower C scores OR = 1.26; 95% confidence interval [CI] = 1.06-1.49) and tau pathology (B score OR = 1.10; 95% CI = 1.08-1.12). DISCUSSION: This is the first study, to our knowledge, finding increased levels of verified AD neuropathology in those with military service. Targeted veteran AD therapies is a pressing need.